A pattern. He pursues big targets (Hillary, Trump), claims he can't find enough dirt on them, gets bigtime face time with media.
Slick would be a word for him. Another would be overly political. And a final one would be not competent enough (or courageous enough), to finish his job.
A political operative, a bum, a rat, a sleaze.
What about IRS targeting conservatives? What about Huma Abedin's connections? What about Clinton Foundation quid pro quo?